Interface DocumentHandler

This interface has been replaced by the SAX2
ContentHandler
interface, which includes Namespace support.

public interface DocumentHandler

Receive notification of general document events.

This module, both source code and documentation, is in the
Public Domain, and comes with NO WARRANTY.
See http://www.saxproject.org
for further information.

This was the main event-handling interface for SAX1; in
SAX2, it has been replaced by ContentHandler, which provides Namespace support and reporting
of skipped entities. This interface is included in SAX2 only
to support legacy SAX1 applications.

The order of events in this interface is very important, and
mirrors the order of information in the document itself. For
example, all of an element's content (character data, processing
instructions, and/or subelements) will appear, in order, between
the startElement event and the corresponding endElement event.

Application writers who do not want to implement the entire
interface can derive a class from HandlerBase, which implements
the default functionality; parser writers can instantiate
HandlerBase to obtain a default handler. The application can find
the location of any document event using the Locator interface
supplied by the Parser through the setDocumentLocator method.

Method Detail

setDocumentLocator

SAX parsers are strongly encouraged (though not absolutely
required) to supply a locator: if it does so, it must supply
the locator to the application by invoking this method before
invoking any of the other methods in the DocumentHandler
interface.

The locator allows the application to determine the end
position of any document-related event, even if the parser is
not reporting an error. Typically, the application will
use this information for reporting its own errors (such as
character content that does not match an application's
business rules). The information returned by the locator
is probably not sufficient for use with a search engine.

Note that the locator will return correct information only
during the invocation of the events in this interface. The
application should not attempt to use it at any other time.

Parameters:

locator - An object that can return the location of
any SAX document event.

endDocument

The SAX parser will invoke this method only once, and it will
be the last method invoked during the parse. The parser shall
not invoke this method until it has either abandoned parsing
(because of an unrecoverable error) or reached the end of
input.

startElement

The Parser will invoke this method at the beginning of every
element in the XML document; there will be a corresponding
endElement() event for every startElement() event (even when the
element is empty). All of the element's content will be
reported, in order, before the corresponding endElement()
event.

If the element name has a namespace prefix, the prefix will
still be attached. Note that the attribute list provided will
contain only attributes with explicit values (specified or
defaulted): #IMPLIED attributes will be omitted.

endElement

The SAX parser will invoke this method at the end of every
element in the XML document; there will be a corresponding
startElement() event for every endElement() event (even when the
element is empty).

If the element name has a namespace prefix, the prefix will
still be attached to the name.

characters

The Parser will call this method to report each chunk of
character data. SAX parsers may return all contiguous character
data in a single chunk, or they may split it into several
chunks; however, all of the characters in any single event
must come from the same external entity, so that the Locator
provides useful information.

The application must not attempt to read from the array
outside of the specified range.

Note that some parsers will report whitespace using the
ignorableWhitespace() method rather than this one (validating
parsers must do so).

ignorableWhitespace

Validating Parsers must use this method to report each chunk
of ignorable whitespace (see the W3C XML 1.0 recommendation,
section 2.10): non-validating parsers may also use this method
if they are capable of parsing and using content models.

SAX parsers may return all contiguous whitespace in a single
chunk, or they may split it into several chunks; however, all of
the characters in any single event must come from the same
external entity, so that the Locator provides useful
information.

The application must not attempt to read from the array
outside of the specified range.